package com.itxiaowu.utils;

import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class Md5Utils {
    /**
     * 使用md5的算法进行加密
     */

    public static String md5(String plainText){

        byte[] secreBytes = null;

        try {
            secreBytes = MessageDigest.getInstance("md5").digest(
                    plainText.getBytes()
            );

        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException("没有md5这个算法");
        }

        String md5code =  new BigInteger(1,secreBytes).toString(16);//16进制

        //如果生成数字未满32为，需要前面补0；
        for(int i = 0; i <32 - md5code.length(); i++){
            md5code = "0" + md5code;
        }

        return md5code;

    }

    public static void main(String[] args) {
        System.out.println(md5("1111"));
    }
}
